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Defining molecular and domain boundaries in the bacteriophage phi29 DNA packaging motor.

ABSTRACT: Cryo-electron microscopy (cryo-EM) studies of the bacteriophage phi29 DNA packaging motor have delineated the relative positions and molecular boundaries of the 12-fold symmetric head-tail connector, the 5-fold symmetric prohead RNA (pRNA), the ATPase that provides the energy for packaging, and the procapsid. Reconstructions, assuming 5-fold symmetry, were determined for proheads with 174-base, 120-base, and 71-base pRNA; proheads lacking pRNA; proheads with ATPase bound; and proheads in which the packaging motor was missing the connector. These structures are consistent with pRNA and ATPase forming a pentameric motor component around the unique vertex of proheads. They suggest an assembly pathway for the packaging motor and a mechanism for DNA translocation into empty proheads.

SUBMITTER: Morais MC

PROVIDER: S-EPMC2615250 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature

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Defining molecular and domain boundaries in the bacteriophage phi29 DNA packaging motor.

Morais Marc C MC Koti Jaya S JS Bowman Valorie D VD Reyes-Aldrete Emilio E Anderson Dwight L DL Rossmann Michael G MG

Structure (London, England : 1993) 20080801 8

Cryo-electron microscopy (cryo-EM) studies of the bacteriophage phi29 DNA packaging motor have delineated the relative positions and molecular boundaries of the 12-fold symmetric head-tail connector, the 5-fold symmetric prohead RNA (pRNA), the ATPase that provides the energy for packaging, and the procapsid. Reconstructions, assuming 5-fold symmetry, were determined for proheads with 174-base, 120-base, and 71-base pRNA; proheads lacking pRNA; proheads with ATPase bound; and proheads in which t ...[more]

PMID: 18682228

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